package com.way.demo.test;

import java.util.Iterator;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.locks.ReentrantLock;

/**
 * @author lipingwei
 * @create 2022-12-07 21:30
 */
public class MianShiTestMain {
    public static void main(String[] args) {

//        String str1="ab";
//        String str2="cd";
//
//        String str3=str1+str2;
//
//        System.out.println(str3 =="abcd");//flase
//
//
//        String str4 ="ab"+"cd";
//        System.out.println(str4=="abcd");//true

        String str1 ="a";
        String str2 = new String("a");
        System.out.println(str1==str2);

        CopyOnWriteArrayList<Object> arrayList = new CopyOnWriteArrayList<>();

        arrayList.add("1");

        Iterator<Object> iterator = arrayList.iterator();

        ReentrantLock reentrantLock = new ReentrantLock();


    }
}
